Fin tube structure



Aug. 27, 1935. E..s. CORNELL, JR 2,012,269

' FIN TUBE STRUCTURE y y Filed No'v. 29, 1932 4 sheets-sheet 1 Aug. 27, 1935. E. s. CORNELL, JR

FINATUBE STRUCTURE Filed Nov. '29, 1952 4 Smeets-sheet 2 INVENTOR.V

BY I l r` Y fa ATTORNEY.

' Aug. 27, 1935. as. coRNELL', JR u 2,012,269 y FIN TUBE STRUCTURE I Filed Nov. 29, 1932 4 sheets-sheet s y Fog. 6.

BY v ATTORNEY.v

Aug. 27, 1935. E. sfoRNELL, .1Rv 2,012,269 l FIN TUBEASTRUGTURE Filed Nov. 29, 1932 4 Sheets-Sheet 4 ATTORNEY.

Patented Aeg. '27, 193s UNITED' STATES PATENT OFFICE FIN TUBE STRUCTURE Edward S. Cornell, Jr., Larchmont, N. Y., assignor to- American Radiator & Standard Sanitary Corporation, New York, N. Y., a corporation of Delaware Applicationnovember 29, 1932, serial No. 644,186

21 claims. (ci. 257-263) My invention relates to improvements in heat exchange apparatus, and the same-has for its object more particularly to provide an extended surface element or structure which is simple in construction, eiiicient in operation, and easy and inexpensive to produce.

' Further, said inventionhas vfor its object t0 provide an extended surface or finned tube element for use as a component part of radiators for house heating purposes, of radiators for cooling systems for Amotor vehicles, as a refriga smooth unbroken wall surface for the tube f are secured together in fluid-tight relation, without generally requiring'a vseparate medium, to

form an elongated tube provided at intervals with extended surface members or fins.

Further, said invention has forits object to provide an element of the character speoied in which the inner edges of the extended surface members or iins are firmly secured in a relatively large mass of metal constituting part of the tubular member of a cooperating contiguousA element. Y

Further, said invention has for its-object to provide an element of the character specified,- formed of sheet metal in which the inner edge of its extendedsurface member and the adjoini ing portion of the wall of its tubular member are firmly clamped in good heat conducting relation between a. pair of annular ribs or flanges extending laterally-outwardly from the wall of the tubular member of a contiguous element.

-Further, said invention has for its object to provide a nned tube structure whose outer wall includes an annularly corrugated or folded portion, having fins between certain of said corrugations or folded portions, and whose inner wall consists of a series of registering cylindrical portions arranged in end to' end relation with the cylindrical portion of one element completely showing the form of the blank resulting fromY the covering the inner ends of the corrugations and foldsof a contiguous element, and forming a substantially smooth, unbroken wall of the tube structure as a whole.

Further, said invention hasfor its object to .5' provide a finned tube structure composed of a series of interengaging elements in which the tubular member `of each element is transversely corrugated to form a series of lrelatively-narrow cylindrical wall portions, and annular ribs lo or flanges extending outwardly therefrom'at substantially right angles to the longitudinal axis of its tubular member between certain of which is secured the finned end or portion of a contiguous Y element. l5

Further, said invention has for its object t0 provide a iinned tube structure in which portions of the cylindrical wall of the tubular member are formed of a singlethicknessofsheet metal, and the annular, laterally-disposed ribs or 20 flanges extending therefrom, which are adapted to embrace the cooperating iins and parts of contiguous elements, comprise double thicknesses of the metal in order to reinforce the tube structure as a whole, and to form fiuid-tight 25 joints between the several cooperating parts thereof.

' Other objects will, in part, be obvious and, in part, be pointed outhereinafter.

To' the attainment of the aforesaid objects- 30 and ends, my invention consists in the novel features of construction, and in the combination, connection and arrangement of parts hereinafter more fully described, and then pointed out in the claims.

In the accompanying drawings- Figure 1 is a side elevation 'showing a radiator incorporating one form of n tube constructed according to, and embodying my said invention;

Fig. 2 anenlarged detail central section of 40 one of the tubular elements forming a constituent part of a iin tube;

Fig. 3 is a similar view showing a number of e connected tubular elements to form-a iin tube;

Fig. 4 is an enlarged detail central section of an 45 end member or ferrule for securing one end of a tube to a header;

Fig. 5 is a similar view showing the manner of securing the opposite end of a tube to its respective header;

Fig. 6 is a face view showing a metal disk from v which a tubular element is formed Fig. 7 is a central section showing a pair of dies mst drawing operation; ss

showing male and female rolls for transversely corrugating the wall of the produced blank and tapering the end thereof;

Fig. l1 is a central section showing a pair of dies and two tubular elements or blanks in position ready for `the rst assembling operation;

Fig. 12 is a View similar to Fig. 10 showing the expanding tool forming the bead upon the upper or inner element and pressing the same into engagement with the inner side of its registering corrugation of the lower or outer element: C

Fig. 13 is a similar view showing the dies having compressed the several corrugations of contiguous elements to duly unite the same, and the mandrel having straightened and swedged the tapering end of the upper or inner element against the inner side or wallof the lower or outer element, and

Fig. 14 is a similar View showing the dies separated horizontally to release the connected tubular elements, and the swedging mandrel retracted.

In said drawings, referring more particularly to Fig. 1, I0 designates a radiator for heat exchange purposes. In said illustration the radiator is shown as comprising two hollow cast metal headers II, IIil provided upon their outer and inner sides, respectively, with bosses I-2, I2.. The bosses I2 upon the outerside of each header are threaded to receive screw plugs i3; and the ends of supply and return pipes Iii, i5, communicating respectively with a source of heating fluid. The bosses I2 upon the inner sides of said headers are designed to receive and hold the ends of the iin tubes I6 which may be secured thereto by any suitable or convenient means; AIn the present instance, and for the purposes of illustration only,

the inner surfaces of the bosses I2ll are provided l circular ange portion 20 extending laterally from one end of said tubular `portion I9. The tubular portion I9, before the element is connected to the remaining or contiguous elements constituting the tube, is provided with a series. of inwardly and outwardly extending corrugations and'folds, 2 I, 22, 23, 24, and terminates at its free end in an inwardly tapering or reducedA end 21 to facilitate the tting thereof into the iianged end ofv a contiguous element. When the tubular portion I9 of one element is fully secured to its next contiguous element the reduced tapering end 21. which has then been expanded against the inner side Vor wall of said contiguous element, will form an apron whose lower end will be substantially in engagement with the upper portion or end' of the apron 21 of said contiguous element, and form therewith a substantially smooth, unbroken inner wall completely enclosing or covering the corrugated portions of said tubular elements, and Serving to reinforce interiorly the tube I6 as a whole..

In forming the tubular element I8 a sheet of metal 3D of copper or other suitable material, as shown at Fig. 6 is subjected to the action of a set of dies 3|, 32, as illustrated at Fig. '7, and a shallow central depression 33 formed; The thus shaped blank is then subjected to the action of a 4similar second set of dies 34, 35, and the central depression 33 of the blank deepened, as shown at Fig. 8. lThe deepened blank is then subjected to a third set of dies 36, 31, and the central depression in the blank still further deepened and the bottom 38)*i punched out by the punch portion 3G, as shown at Fig. 9, producing a blank of the form shown in central section at said Fig. 9 in which the flange 2li, and tubular portion I9 are smooth with the free end of the tubular portion I9 provided with a short inwardly extending flange IQ. The blank as thus developed is next subjected to the action of suitable dies or rolls, such as 39, 45, illustrated at Fig. l0, and the outwardly extending annular beadsor corrugations 22 and 24 formed thereon, and the inwardly-extending ilange, atthe lower or free end of the tubular portion I9, tapered inwardly at 21. By preference the corrugatlon 2411s made somewhat deeper than the corrugations 22, and said corrugations are spaced apart by an intermediate portion 23, and the corrugation 22 separated from the lateral flange 20 by a narrow rounded corrugation 2|. The corrugation 24 is united directly with the upper end of the` downwardly and inwardly tapering end 21 of the tubular portion I 9, as shown at Fig. 2.

Hereupon the blank illustrated at Fig. 2 is secured within the expansible and contraetible members 40 of a lower die 40 with the corrugations 22 and 24 of the blank disposed respectively in the grooves Pand 40d (Fig. 14) formed on the inner face 4I)b of said die 4I). Said die members 40Il are also provided with grooves 40 adapted to receive the corrugation 22 of the lowermost b1ank,-two blanks, as shown at Fig. ll, having been previously connected together.y A third blank is now inserted between the cooperating two-part members 4Il of an upper die 4I, which said two dies 40 and 4I :are normally malntained in separated relation vertically by the springs 42. The members 4|* are contractible to the assembled blanksyand the wall of the tubular portion I9 of the upper blank adjacent the upper end ofthe tapering portion 21 forced outwardly to form the annular corrugation 26, and pressed into intimate contact with the inner side of the annular corrugation 22 of the intermediate blank, as shown at Fig. ll. This operation serves to shorten the length of the tapering portion l1 of the upper blank and bring the lower edge therel of, into engagement with the upper end of the tapering portion of the lower blank. By now' bringingvthe dies 40, 4I fully together as shown at Fig. 13, the interlocking corrugations 2i and 25 will be doubled or attened, and the corrugation 24 of the upper blank and the interlocking corrugations 22 and will be likewise flattened and brought into engagement with opposite sides of the contiguous ange 2liv of the intermediate blank. whereupon a mandrel 44 is forced into Aofinterengaging elements each including an exthe assembled blanks, and the end of ,said tapering portion 21 of the upper blank swedged outwardly against theinner side or Wall of the lower blank, as shown at Fig. i3 thereby bringing the inner sides of said tapering portions 2l into alignment and into close contact with the inner sides of the lower or outer blank to form a substantially smooth, unbroken inner wall for the tube structure as a whole.

lfllhe diesY 40, 4| are then opened, asshown at. Fig. 14, the assembled blanks released and advanced one step, whereupon the operation above described is repeated until 'a suftlcient number of tubular elements have been assembled to form a tube I6 of the desired length. v

It is to be noted that the tubular flanges I 9, as well as the fins 20 may be of any desired shape and size, and that the fins may be separated more 2. A n tube structure comprising a plurality of interengaging transversely corrugated elements each including an extended surface member, a tubular ilange extending therefrom, 'and a pair ofV annular ribs formed integrally therewith and extending laterally outwardly from said tubular ange vandrmly embracing therebetween the inner edge of the extended surface member and the adjoining wall portion of its tubular flange of a contiguous element, substantially as specified'. Y

`3. A fin tube structurev comprising a plurality tended surface member having an aperture therein, and a transversely corrugated tubular member extending from said aperture; certain adjacent corrugations of each .tubular member being collapsed and embracing therebetween the apertured portion of the extended surface member of a contiguous element, substantially as specified. l

4. A fm tube structure comprising a plurality of interengaging tubular elements each includingan extended surface member; each of said tubular elementsl having a plurality of parallel, at, annular ribs in laterally interfolded cooperating :dat annular ribs of contiguous elements to form fluid-tight joints between said elements, substantially as specified. 5. A fin tube structure comprising -a plurallty of interengagin'g tubular elements each including an extended surface member; each'of said tubular elements having a plurality of inwardly and outwardly projecting parallel annular folds engagingwith cooperating annular folds of contiguous elements to-'form fluid-tight joints between said elements, substantially as specified.

6. `A flntube structure comprising a; plurality of inter-engaging tubular elements each including an extended surface member; each of said tubuto form fluid-tight joints between said elements, substantially as specified.

.'1. A fin tube structure comprising-a plurality of inter-engaging tubular elements each including an extended surface member; each' of said tubular elements having a plurality of collapsed an an extended surface member; each oi said tubular-elements having a plurality of annular corrugations, said. corrugations having certain of their inner and outer bends collapsed to form parallel annular ribs engaging cooperating collapsed annular corrugations and parts of contiguous elements to form fluid-tight joints between the same, substantially as specified.

9. A iin tube structure comprising al plurality of interengaging tubular elements formed of sheet metal each including an extended Surface member; each of said tubular elements rhaving 'a plurality of annular corrugations, and certain of said corrugations having their bends collapsed to form laterally extending ribs confining therebetween and intimately embracing cooperating ribs vand parts of contiguous elements to form uidtight joints between the same, substantially as specified.

10. A iin tube structure comprising a plurality of interengaging tubular elements formed integrally of 'sheet metal each including an extended sur ace member; each of said tubular elements havinga plurality' of annular corrugations, and certain of said corrugations having theirbends collapsed to form flat ribs extending at substantially right angles to the longitudinal axis of the velement and intimately embracing therebetween 'cooperating ribs and parts of contiguous elements to form fluid-tight joints between the same, substantially as specified.

1l. A fin tube structure comprising a plurality of interengaging tubular elements formed of sheet metal each including an extended surface member'extending from one end thereof; each of said tubular elements having a plurality of annular corrugations, and certain of said corrugations havingV their bends collapsed to form ilat parallel ribs extending at substantially right angles to the longitudinal axis of the element and intimately embracing therebetween cooperating ribs v.and parts ofjcontiguous elements to form fluid-tight Joints between the same, substantially as specified. v

12. A iin tube structure comprising a plurality vof interengaging elements formed of sheet metal their bends collapsed to form laterally extendingv ribs confining therebetween and intimately embracing cooperating ribs and parts of contiguous elements to Aform fluid-tight joints between thc same, substantially as specified.

13. A nn tube structure comprising a plurality of interengaging tubular elements formed of sheet metal each including an extended surface member extending laterally' from one end thereof;vv each of said tubular elements ,having-a plurality of relatively-narrow cylindrical w'all portions and 'lol a plurality lof annular corrugations extending therefrom, and certain of said corrugations having their bends flattened to form nat, parallel ribs disposed at substantially right angles to the longitudinal axis of the element and intimately embracing cooperating ribs and corrugations of contiguouselements to form fluid-tight joints between the same, substantially as specified.

14. A fin tube structure comprising a plurality of interengaging elements each including an extended surface member having an aperture therein and a transversely corrugated tubular member extending from said aperture; said member having a portion of its wall along Athe edge of said -aperture folded against one side of said extended surface member to form a thickened edge, and certain of the corrugations of each tubular member being flattened to form parallel ribs closely embracing the thickened apertured portion of the extended surface member of a contiguous element, substantially as specified.

15. A fin tube structure comprising a plurality of interengaging elements each including an extended surface member andfa tubular flange' extending therefrom having a transversely corrugated portion interfolded with the cooperating corrugated portion of contiguous elements,l and a tubular apron portion extending from said interfolded corrugated portion; the apron portions of said elements, when assembled, forming the inner wall of the tube structure as a whole, substantially elements, and a tubular apron portion extending from said interfolded corrugated portion and completely covering the' inner corrugated wall of the contiguous element and forming a substantially smooth, unbroken wall of the tube structure as a whole] substantially as specified.

17. A n tube structure comprising a plurality of interengaging elements each including an extended surface member, and a tubular fiange extending therefrom; said tubular flange having a transversely corrugated portion interfclded with the registering corrugated portions of contigu- .ous elements,V and a smooth, substantially cylinamazes drical portion extending from said` interfolded corrugated portion registering and cooperating with registering corrugations of a contiguous section, and a tubular apron portion extending from said corrugated portion; the tubular apron portions of said elements meeting substantially in end to end relation and forming the smooth, substantially unbroken inner wall of the tube structure as a whole, substantially as specified.

'19. A n tube structure comprising a plurality of interengaging elements each including an extended surface member and a tubular fiange extending therefrom; said tubular flange having a series of parallel, horizontal ribs extending therefrom angularly with respect to the normal of said tubular flange and annularly interfolded with the registering flange portions of 4contiguous elements, substantially as specified.

20. A fin tube structure comprising a plurality of interengaging elements each including an extended surface member and a tubular flange extending therefrom; said tubular flange having the alternate exterior and interior surfaces of its wall portion in engagement, respectively, with the inte'rior and exterior surfaces of the wall portions of contiguous elements and annularly interfolded therewith, substantially as specified.

21. In a n tube structure including a plurality of interengaging elements, a terminal member comprising a tubular portion and a pair of annular ribs arranged in spaced relation to each other intermediate the ends of said tubular portion, and each end of said tubular portion extending from said ribs terminating in a smooth cy- CERTIFICATE or CCRRECTICN. Patent Nb. 2,012,269. August a?, 1935.

EDWARD s. CORNELL, JR.

It is hereby Certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, first Column, line 57, Claim 4, after "ribs" strike out "in" and same line, after "nterfoldedW-nsert the word with; and that the said Letters Patent should` be read with these Corrections therein that the same may Conform to the record of the Case in the Patent Office.

Signed and sealed this 16th day of March, A. D. 1937.

' Henry Van Arsdale (Seal) Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 2,012,269, August 27, 1935.

EDWARD s. CORNELL, JR.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page l, first column, line 2.9, after "separate" insert sealing; and line 51,- after the syllable "tion" strike out the comma; same page, second column, line 2, after "element" strike out the comma; line 44, strike out the word "connected" and insert the same after "elements", same line;' and line 51, after "disk" insert the words or plate; and that the said Letters Patent should be read with them corrections therein that the same may conform to the record of the case in th Patent Office.

Signed and sealed this 3rd day of March, A. D. 1936.

Leslie Frazer (Seal) Acting Commissioner of Elementse 

